cool book

But my eyes work really well.

Human retinas do local line and texture pre-processing, because they are not simple pixel senders. That affects my schematics, the way things line up on the sheet. I'd expect shrimp to draw pretty ugly schematics (like some I see here.)

Are they faster? A hawk attacks another bird at high velocity and often misses. Fast cats do that too. They are sort of unguided missiles in the terminal phase.

Hawks draw terrible schematics and don't assemble machinery well.

Thay are certainly important parts of the system. Try hunting or farming or coding blindfolded.

What's the selection advantage of bad eyesight?

Seeing a brief image in bed with my head under a sheet isn't much of a threat to survival. It's actually cool.

I envision systems and schematics that aren't real either. Yet.

Don't you?

I have phosphenes and migraine auras too. The auras are possibly dangerous, especially when driving. Luckily, I don't get the headaches. Lots of people have migraines, fewer have auras first, very few get the aura without the headache.

mandag den 22. marts 2021 kl. 18.10.20 UTC+1 skrev snipped-for-privacy@highlandsniptechnology.com:

you get left at home "watching" the women while the guys with good eyesight go hunting ;)

See Appendix for details.

;-)

How might it explain that? How much better might our vision be if it didn't have to waste power overcoming its crappy features?

But the point in question is... Imagine[1] how much better it would be if we didn't have a blind spot and the brain didn't have to /attempt/ to work around the crappy retina "design".

So what?

They reveal "suboptimal" features in our visual system.

No outrage, merely anticipation - waiting for you to give us a clue as to how the suboptimal design might be better.

But you won't answer that, of course.

On 2021-03-22 15:52, snipped-for-privacy@highlandsniptechnology.com wrote: [Snip!]

Certainly not *every* eye is better than ours. However, the question is valid: How did vertebrates end up with such an eye?

Jeroen Belleman

The 'Why' question should be addressed to a rational entity, who understands reasoning, and can give reasons.

Evolution is not a rational entity. You have made an obvious mistake again, because a reasoning being (who is presumably reading the question) cannot account for the "decision" which is more correctly described as a branching path.

No aspect of reality exists which could provide a 'Why' answer. The branching path can be described, however.

Larkin himself answered that: he claims to be trolling. Strictly speaking that requires the troller to understand why their statements are a troll; I'm not convinced that is the case with Larkin.

On 21/03/21 19:37, snipped-for-privacy@highlandsniptechnology.com wrote: > On Sun, 21 Mar 2021 13:41:26 -0500, John S snipped-for-privacy@invalid.org > wrote: >> So you're just trolling. > Certainly.

On Monday, 22 March 2021 at 10:25:07 UTC-7, Martin Brown wrote: ..

:-)

OK, not every eye was better, but only vertebrates (and all vertebrates) evolved the very complex inverted structure, from our invertebrate ancestors, against an "obvious" negative selection gradient.

People claim they have explained this so won't again. The explanations seemed like outright rejection of the concept of evolution to me. That includes calling me stupid, since I'm fairly evolved.

We ended up with this kind of eye by the usual process, selection for survival.

I've enjoyed it.

All vertebrates have the superior inverted retina design. Raptors too.

The discussion is about how *vertebrate* eyes are badly designed and inferior.

I suggested that the vertebrate eye design is actually excellent, because evolution made it excellent. People mostly diagree.

Raptors have inverted retinas too.

I know that raptors have the same basic eye-structure as humans but their visual acuity is far better than humans.

My comments were not about inverted vs non-inverted retina but whether good eyesight in humans was a predominant factor in reproductive advantage - I maintain that it was not as powerful as in other animals; particularly ones such as raptors.

kw

On Monday, 22 March 2021 at 14:20:50 UTC-7, John Larkin wrote: ...

You persist in changing the subject of the discussion.

I don't see people disagreeing with the fact that the vertebrate eye with the aid of evolution can achieve very good results.

I do see statements that the basic architecture has a limitation regarding the light path being obstructed by the positioning of the photosensors and nerves and any "designer" starting with a clean slate would not have arranged it as such without some reason that is not obvious to anyone, except you it seems.

You have not explained why it is superior with any convincing arguments.

With camera sensors we did in fact initially select a similar organization but we had good reasons and once technology allowed have altered the light path to bring improvements.

The difference is that we had the luxury of not being under the same restrictions as incremental evolution. ...

kw

And the web for more details:

What was this "gradient"?

The concept of evolution involves small improvements in existing organs with the option of repurposing organs that have become redundant or duplicated to handle new functions. Each organism along the path has to function well enough to survive and reproduce. Ripping up the retina and putting its blood supply and its connections to the rest of the nervous system behind the retina , rather than in front of it, isn't in the evolutionary repertoire.

You aren't stupid - in the sense of not being able to understand - but you are ill-informed, and you do have a foolish tendency to stay ill-informed after you have been exposed to better information.

This seems to be mainly due to vanity, rather than stupidity. Evolution seems to have left you with a higher feeling of self-worth than would have been entirely otpimal.

But a lot of other features were being selected for at the same time. and each generation was selected for survival. Evolution isn't kind to proof-of-principle prototypes.

My error - that was a typo. I obviously meant "vertebrate".

The main disagreement was about the basic optical system not about evolution making a good job with what it had.

...

On Monday, 22 March 2021 at 14:06:51 UTC-7, John Larkin wrote: ..

What "obvious" negative selection gradient?

Which explanations? I don't recall any that rejected evolution.

What is good for survival is not always obvious.

Yes, incremental improvements over hundreds of millions of years with multiple changes of the external environment and forcing functions.